Introduction to SSH

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Introduction to SSH

• Making connections

donna Bair-Mundy
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Information security measures (1)
Physical securityprotect against theft and
physical damage
Anti-virus software
Firewallsprovide protection from known external
attacks
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Information security measures (2)
Access controlscontrol who can log onto the
computer and which directories or files a person
who logs on can access
Intrusion detection
Encryptionprotect sensitive information and
prevent session hijacking
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Why do we need encryption?
server
hub
packet sniffer
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What is SSH?
Secure shell program
Encrypted transmissions
Telnet-like utility
Secure File Transfer Protocol
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Secure shell client
server
file1 file2
ls
client
file1 file2
ls
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Encryption
Encryption method
RSA, ECC, DES, AES
Encryption key
ximop-qykam-lazyv
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Encryption methods
Public-key encryption
Symmetric-key encryption
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Public-key encryption
server
public key (encodes)
client
private key (decodes)
client
client
client
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Public-key encryption (cont'd)
server
server'spublic key
symmetric key
lock
unlock
server'sprivate key
symmetric key
client
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Symmetric-key encryption
server
message
symmetric key
symmetric key
client